阻抗角对交直流输电系统过电压影响的研究  

Impact of Impedance Angle on AC/DC Transmission System Over-voltage

作　　者：白建勋[1] 杨洪耕[1] 王鹏飞[1] 

机构地区：[1]四川大学电气信息学院,成都610065

出　　处：《华东电力》2012年第5期784-788,共5页East China Electric Power

基　　金：国家自然科学基金支持项目(51077095)~~

摘　　要：直流系统与弱交流系统相连会出现高暂态过电压,目前大多采用短路比进行交互影响分析,其主要考虑的是交流系统等值阻抗模值的影响,并未考虑阻抗角与系统过电压的关系,具有一定的局限性。在CIGER标准模型的基础上搭建两馈入直流系统,保持短路比不变,分别研究强耦合和弱耦合情况下的交流系统本身的阻抗角以及耦合阻抗角对受端换流母线暂态过电压的影响。分析结果表明,耦合阻抗角对系统暂态过电压的影响较小,而适当减小交流系统本身阻抗角有利于减小故障后的过电压,改善故障对系统的冲击,提高系统稳定性。High-level transient over-voltage may occur when DC system is connected to weak AC system, and the short circuit ratio （SCR） is usually adopted for DC-AC interaction analysis. However this method has certain limitations because it only focuses on the impact of modulus value of AC system equivalent impedance, ignoring the relationship between the system over-voltage and the impedance angle. In this paper, a two-infeed DC system was set up on the basis of CIGER standard model. With the short circuit ratio fixed, the impacts of AC system impedance angle and cou- pling impedance angle were studied on the transient over-voltage of the receiving system commutation bus in the case of strong coupling and weak coupling, respectively. Analysis results show that coupling impedance angle has little effect on system transient over-voltage, and that the fault over-voltage tends to decline when the AC system equivalent impedance is reduced. Thereby, the impact of failures on system can be alleviated and system stability can be improved.

关 键 词：直流系统 弱交流系统 短路比 阻抗角 暂态过电压 

分 类 号：TM712[电气工程—电力系统及自动化]